Ok have never heard recapitulation used as evidence for evolution.
http://www.pathlights.com/ce_encyclopedia/17rec01.htm
I assume this is something creationists use to attack evolution when scientist don’t even use it as evidence. So what is the story with recapitulation and evolution?
Sorry for the typos.
Not much of a story. Recpaitulation is basically the idea that primitive features are retained in juvenile creatures, such as a tadpoel retaining the gills of fish. It had a lot of support 100 years ago, but is now considered far less credible. It does still hold true in some instances, but there have been shown to be too many exceptions for it to be particulaly useful today. One of the few uses it does get is in the construction of cladistic relationships. A feature found only in a juvenile is still considered to exist withing that clade, but is considered to be primitive.
So it’s basically a scientific theory that has been discredited and abandoned in the face of fresh evidence. Nothing new here.
Blake do you have any links to back up recapitulation has been discredited? I am not calling your statements into question; it is just every page I find through Google in very creationist and not really that scientific.
Nah, can’t help you sorry. I do recall that Gould mentioned it as an example of discredited theory in one of his essays, so that might give you a starting point.
And having said that I put ‘Gould Recapitualtion’ into Google, and the first site says
Looks like there are heaps of other non-Creationist sites using that search as well.
Thanks.
If you really want to wade through this swamp, find a copy of Gould’s Ontogeny and Phylogeny. (This is not one of Gould’s breezier books.)
The primary sticking point regarding recapitulation was the phrase coined from a statement made by Ernst Haeckel, “Ontogeny is the short and rapid recapitulation of phylogeny. . . During its own rapid development. . . an individual repeats the most important changes in form evolved by its ancestors during their long and slow paleontological development.” in his 1866 work, Generelle Morphologie die Organismen. From this, the aphorism was coined “Ontogeny recapitulates Phylogeny.”
This “law” was widely embraced by the students of Lamarck, who saw in it the passing of acquired characteristics from one generation to the next. (I am being unfair to actual Lamarckian explanations in the interest of brevity.)
While some Darwinists accepted the “law” of recapitulation and attempted to work with it, it was never a serious cornerstone of Darwinian theory. When Mendelian genetics was joined to Darwinian descent with modification, the whole notion of recapitulation became untenable.
The reason that recapitulation is no longer accepted lies in the description of what it actually entailed. The notion of recapitulation (especially as embodied in Haeckel’s dictum) was that each earlier stage of an an ancestor creature’s adult form was displayed in the juvenile (or embryonic) form of the modern descendent. Thus, finding gill slits in embryonic humans was supposed to indicate the earlier adult fish form from which humans eventually evolved. However, the gill slits of embryonic humans do not match the gill slits of mature fish. Rather, the gill slits of embryonic humans are homologous to the embryonic gill slits of all vertebrates–including fish, amphibians, and reptiles. This is not recapitulation, but simply the preservation of an earlier form at the same stage of development.
One reason that Creationists make such a big (and unnecessary) deal about recapitulation (and Haeckel and his fudged drawings) is that, for some reason, Haeckel’s drawings made it into textbooks for decades after his work had been dismissed by the actual biologists studying evolution. I am not sure why Haeckel and his drawings continued in print for so long (aside from the general dumbness of textbooks), but the Creationists have transferred the legitimate criticism of including Haeckel in textbooks to the illegitimate attempt to criticize evolutionary theory based on the errors that appeared in the textbooks.